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How to use SqlBulkCopy.WriteToServer to Bulk Insert rows into SQL Server , ONLY if Not Exists

We are using SqlBulkCopy.WriteToServer to bulk insert to SQL Server and works very well. However, it fails when a record already exists. What we need is to "ignore" those rows that already exist, and insert the non-existing ones.
SqlException: Violation of PRIMARY KEY constraint 'PK__Pharmacy__3214EC072C1E8537'.
Cannot insert duplicate key in object 'dbo.Pharmacy'. The duplicate key value is (797cba76-8bbd-4dbd-a360-4f8e8a6ef85b)
How can we use SqlBulkCopy.WriteToServer to insert rows, if they do not exist, without breaking or failing.
try
{
// Write from the source to the destination.
bulkCopy.WriteToServer(dt);
}
catch (Exception ex)
{
throw new Exception($"BulkInject error in {dt.TableName}", ex);
}
Update:
It's important to mention that this works well most of the time, 98% of the time and bulk inserting properly. Just 2% of the time, some rows already exist that will cause the bulk insert to fail.
What we need: we need to "ignore" those rows if exist
What we do: Data transfer of source database to dest db. It's not a full transfer. We transfer a subset of the source data. The dest db is NOT empty. It already contains data. So update is NOT an option. We need to insert if not exists.
There are around 30 tables that we do bulk insert from source to dest db. So we have a generic function that does field mapping, bulk inserting, etc... it's the same function that handles all these tables.
Again, what we need: We are using SqlBulkCopy.WriteToServer and we need to "ignore" rows if they exist. Thanks

SqlBulkCopy as the name suggest is for copying (inserting) bulk records and it cannot perform update operation. Hence comes Table Valued Parameter to the rescue, which allows us to pass multiple records using a DataTable to a Stored Procedure where we can do the processing...
SQL Server 2008(or higher) came up with a nice function called MERGE, which allows to perform INSERT operation when records are not present and UPDATE when records are present in the table.
You can create a User Defined Table Type in SQL Server
Finally the following similar kind of stored procedure is created which will accept the whole DataTable as parameter and then will insert all records into the table that are not present in the table and the one that already exists will be updated.
CREATE PROCEDURE [dbo].[Update_Pharmacy]
#tblCustomers CustomerType READONLY
AS
BEGIN
SET NOCOUNT ON;
MERGE INTO Customers c1
USING #tblCustomers c2
ON c1.CustomerId=c2.Id
WHEN MATCHED THEN
UPDATE SET c1.Name = c2.Name
,c1.Country = c2.Country
WHEN NOT MATCHED THEN
INSERT VALUES(c2.Id, c2.Name, c2.Country);
END
The performance will be less as Bulk Copy Utlity but somehow it is one of option i have used while working on a reporting database from realtime DB.

Fastest way to insert 1 million rows in SQL Server [duplicate]

This question already has answers here:
Insert 2 million rows into SQL Server quickly
(8 answers)
Closed 8 years ago.
I am writing a stored procedure to insert rows into a table. The problem is that in some operation we might want to insert more than 1 million rows and we want to make it fast. Another thing is that in one of the column, it is Nvarchar(MAX). We might want to put avg 1000 characters in this column.
Firstly, I wrote a prc to insert row by row. Then I generate some random data for insert with the NVARCHAR(MAX) column to be a string of 1000 characters. Then use a loop to call the prc to insert the rows. The perf is very bad which takes 48 mins if I use SQL server to log on the database server to insert. If I use C# to connect to the server in my desktop (that is what we usually want to do ), it takes about more than 90mins.
Then, I changed the prc to take a table type parameter as the input. I prepared the rows somehow and put them in the table type parameter and do the insert by the following command:
INSERT INTO tableA SELECT * from #tableTypeParameterB
I tried batch size as 1000 rows and 3000 rows (Put 1000-3000 rows in the #tableTypeParameterB to be inserted for one time). The performance is still bad. It takes about 3 mins to insert 1 million rows if I run it in the SQL server and take about 10 mins if I use C# program to connect from my desktop.
The tableA has a clustered index with 2 columns.
My target is to make the insert as fast as possible (My idea target is within 1 min). Is there any way to optimize it?
Just an update:
I tried the Bulk Copy Insert which was suggested by some people below. I tried use the SQLBULKCOPY to insert 1000 row and 10000 row at a time. The performance is still 10 mins to insert 1 million row (Every row has a column with 1000 characters). There is no performance improve. Is there any other suggestions?
An update based on the comments require.
The data is actually coming from UI. The user will change use UI to bulk select, we say, one million rows and change one column from the old value to new value. This operation will be done in a separate procedure.But here what we need to do is that make the mid-tier service to get the old value and new value from the UI and insert them in the table. The old value and new value may be up to 4000 characters and the average is 1000 characters. I think the long string old/new value slow down the speed because when I change the test data old value/new value to 20-50 characters and insert is very fast no matter use SQLBulkCopy or table type variable

I think what you are looking for is Bulk Insert if you prefer using SQL.
Or there is also the ADO.NET for Batch Operations option, so you keep the logic in your C# application. This article is also very complete.
Update
Yes I'm afraid bulk insert will only work with imported files (from within the database).
I have an experience in a Java project where we needed to insert millions of rows (data came from outside the application btw).
Database was Oracle, so of course we used the multi-line insert of Oracle. It turned out that the Java batch update was much faster than the multi-valued insert of Oracle (so called "bulk updates").
My suggestion is:
Compare the performance between the multi-value insert of SQL Server code (then you can read from inside your database, a procedure if you like) with the ADO.NET Batch Insert.
If the data you are going to manipulate is coming from outside your application (if it is not already in the database), I would say just go for the ADO.NET Batch Inserts. I think that its your case.
Note: Keep in mind that batch inserts usually operate with the same query. That is what makes them so fast.

Calling a prc in a loop incurs many round trips to SQL.
Not sure what batching approach you used but you should look into table value parameters: Docs are here. You'll want to still batch write.
You'll also want to consider memory on your server. Batching (say 10K at a time) might be a bit slower but might keep memory pressure lower on your server since you're buffering and processing a set at a time.
Table-valued parameters provide an easy way to marshal multiple rows
of data from a client application to SQL Server without requiring
multiple round trips or special server-side logic for processing the
data. You can use table-valued parameters to encapsulate rows of data
in a client application and send the data to the server in a single
parameterized command. The incoming data rows are stored in a table
variable that can then be operated on by using Transact-SQL.
Another option is bulk insert. TVPs benefit from re-use however so it depends on your usage pattern. The first link has a note about comparing:
Using table-valued parameters is comparable to other ways of using
set-based variables; however, using table-valued parameters frequently
can be faster for large data sets. Compared to bulk operations that
have a greater startup cost than table-valued parameters, table-valued
parameters perform well for inserting less than 1000 rows.
Table-valued parameters that are reused benefit from temporary table
caching. This table caching enables better scalability than equivalent
BULK INSERT operations.
Another comparison here: Performance of bcp/BULK INSERT vs. Table-Valued Parameters

Here is an example what I've used before with SqlBulkCopy. Grant it I was only dealing with around 10,000 records but it did it inserted them a few seconds after the query ran. My field names were the same so it was pretty easy. You might have to modify the DataTable field names. Hope this helps.
private void UpdateMemberRecords(Int32 memberId)
{
string sql = string.Format("select * from Member where mem_id > {0}", memberId);
try {
DataTable dt = new DataTable();
using (SqlDataAdapter da = new SqlDataAdapter(new SqlCommand(sql, _sourceDb))) {
da.Fill(dt);
}
Console.WriteLine("Member Count: {0}", dt.Rows.Count);
using (SqlBulkCopy sqlBulk = new SqlBulkCopy(ConfigurationManager.AppSettings("DestDb"), SqlBulkCopyOptions.KeepIdentity)) {
sqlBulk.BulkCopyTimeout = 600;
sqlBulk.DestinationTableName = "Member";
sqlBulk.WriteToServer(dt);
}
} catch (Exception ex) {
throw;
}
}

If you have SQL2014, then the speed of In-Memory OLTP is amazing;
http://msdn.microsoft.com/en-au/library/dn133186.aspx

Depending on your end goal, it may be a good idea to look into Entity Framework (or similar). This abstracts out the SQL so that you don't really have to worry about it in your client application, which is how things should be.
Eventually, you could end up with something like this:
using (DatabaseContext db = new DatabaseContext())
{
for (int i = 0; i < 1000000; i++)
{
db.Table.Add(new Row(){ /* column data goes here */});
}
db.SaveChanges();
}
The key part here (and it boils down to a lot of the other answers) is that Entity Framework handles building the actual insert statement and committing it to the database.
In the above code, nothing will actually be sent to the database until SaveChanges is called and then everything is sent.
I can't quite remember where I found it, but there is research around that suggests it is worth while to call SaveChanges every so often. From memory, I think every 1000 entries is a good choice for committing to the database. Committing every entry, compared to every 100 entries, doesn't provide much performance benefit and 10000 takes it past the limit. Don't take my word for that though, the numbers could be wrong. You seem to have a good grasp on the testing side of things though, so have a play around with things.

Sync MySQL and MSSQL databases through windows service

I must sync 2 tables of two databases one of which is a MSSQL and the other one MySQL. I have to do this through a Windows Service. I currently have created a Windows Service, and what I currently have added to the service is : getting the data from the MySQL database and inserting it into a Data Adapter from which I plan to move the data to the MSSQL database using an insertion through transaction.Can you tell me what is the best approach to this problem and if what I'm doing right now is on the right track, first time I'm doing such a thing.

Well, probably there is a couple ways to solve this. You didn't mention about count and size of your tables, desired synchronization frequency so my answer might be not 100% relevant. Anyway my proposal is:
Each table should have additional column - SyncDate (TIMESTAMP) which by default is null.
Sync logic which is implemented in Windows Service periodically checks each table if there is some data to sync by executing query like this (use pure IDataReader for performance reasons):
SELECT * from TEST_TABLE where SyncDate is null
If above statement returns data then:
collect package of rows to insert (for example 500 rows)
begin transaction on target database and execute insert statement for collected package (set value for column SyncDate to DateTime.Now)
when insert is complete execute statement like this in source db:
UPDATE TEST_TABLE SET SyncDate = #DateTime.Now where ID_PRIMARY_KEY IN (IDENTIFIRES FROM PACKAGE)
commit transaction
collect another packages and repeat algorithm until DataReader provides data
Above algorithm should be applied on both databases
Probably your database has foreign keys so you have to remember that dependant tables should be synchronized in valid order
Wherever it possible you can benefit from multi threading

For this kind of job, SQL Server Integration Services is the way to go.
SSIS is made to Extract, transform, and load data. (ETL process)
You design a worklow with each transformation step of your data, from MySQL to MSSQL.
You then create a job and configure its schedule, and it will be executed by SQL Server.
No need to develop something from scratch and hard to maintain.

If you are already at a point where you are ready to move the MySQL data to SQL. I would suggest you put them on a separate table and issue a Merge command to merge the data. Make sure that you flag back the data that has been updated so you can now get them back and push to MySQL:
MERGE TableFromMySQL AS TARGET USING TableFromSQL AS SOURCE
ON (TARGET.PrimaryKey = SOURCE.PrimaryKey)
WHEN Matched AND (TARGET.Field1 <> SOURCE.Field1
OR TARGET.Field2 <> SOURCE.Field2
OR .. put more field comparison here that you want to sync
THEN
UPDATE
SET TARGET.Field1 = SOURCE.Field1,
TARGET.Field2 = SOURCE.Field2,
//flag the target field as updated
TARGET.IsUpdated = 1,
TARGET.LastUpdatedOn = GETDATE()
WHEN Not Matched
THEN
INSERT(PrimaryKey, Field1, Field2, IsUpdated, LastUpdatedOn)
VALUES(SOURCE.PrimaryKey, SOURCE.Field1, SOURCE.Field2, 1, GETDATE());
At this point, you can now query the MySQL table with IsUpdated = 1 and push all values to MYSQL database. I hope this helps.

If you add the mySql database as a linked server (sp_addlinkedserver) then I think you could do the following in a stored proc on your MS SQL database:
insert table1(col1)
select col1
from openquery('MySqlLinkedDb','select col1 from mySqlDb.dbo.table2')

If you have to do this through a Windows Service, I am curious how you are receiving the data from MySQL? What is initiating the call to the service and what form is the data passed in? Are you getting changes or are you getting a couple refresh of the data?
If you receive a DataTable or some other kind of IEnumerable and its a complete refresh, for example, you could use SqlBulkCopy.WriteToServer(). That would be the fastest and most efficient.
Tom

How to copy and validate data from one table (all varchar) to another (typed) in C#?

[note: needs to be in code as can't use SSIS or similar]
I need to bulk copy data from one database to another using C# and EF probably - though this isn't cast in stone.
The problem is that the source data is all in varchar(max) and I want the destination in correct data types. The source is historical from an old ETL job that works very well and I can't get replaced. The most common issue I have seen is alpha's in numeric fields - e.g. "none" in a money field. These are fine in the source since it's all varchar.
I'd like to copy the data and validate it:source -> validate -> destination
in the simplest way possible. If validation fails then I need to know the exact row that failed (and ideally WHAT failed) so that it can be manually fixed in the source, and the data re-copied.
There are around 50 tables ranging between 10 and 1.7M rows! So speed is important as well.
What would be a sensible way to approach this? Create DTO's, validation attributes and automap? Two EF entities and map across row by row and validate each? SPROC and manual insert?

Do it in T-SQL with a linked server.
I.e.:
--begin a transaction to wrap validation and load
BEGIN TRAN
--Validate that no tickets are set to closed without a completion date
SELECT *
FROM bigTableOnLocalServer with (TABLOCKX) -- prevent new rows
WHERE ticketState = '1' /* ticket closed */ and CompletionDate = 'open'
--if validation fails, quit the transaction to release the lock
COMMIT TRAN
--if no rows in result set 1, execute the load
INSERT INTO RemoteServerName.RemoteServerDBName.RemoteSchema.RemoteTable (field1Int, Field2Money, field3text)
SELECT CAST(Field1 as int),
CASE Field2Money WHEN 'none' then null else CAST(Field2Money as money) END,
Field3Text
FROM bigTableOnLocalServer
WHERE recordID between 1 and 1000000
-- after complete, commit the transaction to release the lock
COMMIT TRAN
If you cannot communicate directly between the servers, still do the validation in SQL, but use a C# client to write the data to disk and hit the Bulk insert function on the destination server. Since the C# component would do nothing more than transport the data, I would just go straight to a format usable by BULK INSERT, à la CSV.

Questions About SQl BulkCopy

I am wondering how can do a mass insert and bulk copy at the same time? I have 2 tables that should be affect by the bulk copy as they both depend on each other.
So I want it that if while inserting table 1 a record dies it gets rolled back and table 2 never gets updated. Also if table 1 inserts good and table 2 an update fails table 1 gets rolled back.
Can this be done with bulk copy?
Edit
I should have mentioned I am doing the bulk insert though C#.
It sort of looks like this but this is an example I been working off. So I am not sure if I have to alter it to be a stored procedure(not sure how it would look and how the C# code would look)
private static void BatchBulkCopy()
{
// Get the DataTable
DataTable dtInsertRows = GetDataTable();
using (SqlBulkCopy sbc = new SqlBulkCopy(connectionString, SqlBulkCopyOptions.KeepIdentity))
{
sbc.DestinationTableName = "TBL_TEST_TEST";
// Number of records to be processed in one go
sbc.BatchSize = 500000;
// Map the Source Column from DataTabel to the Destination Columns in SQL Server 2005 Person Table
// sbc.ColumnMappings.Add("ID", "ID");
sbc.ColumnMappings.Add("NAME", "NAME");
// Number of records after which client has to be notified about its status
sbc.NotifyAfter = dtInsertRows.Rows.Count;
// Event that gets fired when NotifyAfter number of records are processed.
sbc.SqlRowsCopied += new SqlRowsCopiedEventHandler(sbc_SqlRowsCopied);
// Finally write to server
sbc.WriteToServer(dtInsertRows);
sbc.Close();
}
}

I am wondering how can do a mass
insert and bulk copy at the same time?
I have 2 tables that should be affect
by the bulk copy as they both depend
on each other. So I want it that if
while inserting table 1 a record dies
it gets rolled back and table 2 never
gets updated. Also if table 1 inserts
good and table 2 an update fails table
1 gets rolled back. Can this be done
with bulk copy?
No - the whole point of SqlBulkCopy is to get data into your database as fast as possible. It will just dump the data into a single table.
The normal use case will be to then inspect that table once it's imported, and begin to "split up" that data and store it into whatever place it needs to go - typically through a stored procedure (since the data already is on the server, and you want to distribute it to other tables - you don't want to pull all that data back down to the client, inspect it, and then send it back to the server one more time).
SqlBulkCopy only grabs a bunch of data and drops it into a table - very quickly so. It cannot split up data into multiple tables based on criteria or conditions.

You can run bulk inserts inside of a user defined transaction so do something like this:
BEGIN TRANSACTION MyDataLoad
BEGIN TRY
BULK INSERT ...
BULK INSERT ...
COMMIT TRANSACTJION MyDataLoad
END TRY
BEGIN CATCH
ROLLBACK TRANSACTION
END CATCH
However, there may be other ways to accomplish what you want. Are the tables empty before you bulk insert into them? When you say the tables depend on each other, do you mean that there are foreign key constraints you want enforced?